Method of making turbomachine blading



Oct. 21, 1958 r R. E. HANSEN 2,856,675

METHOD OF MAKING TURBOMACHINE BLADING Filed Nov. 8, 1954 5 Sheets-Sheet 1 Oct.'21, 1958 R. E. HANSEN METHOD OF MAKING TURBOMACHINE BLADING 3 SheetsSheet 2 JNVENTOR. flare/c 6: 167.5%? BY Filed Nov. 8, 1954 Z4 W 2% ATTORNEY ACHINE BLADING s Sheets-Sheet s Oct. 21, 1958 R. E. HANS METHOD OF" MAKING TURBOM Filed Nov. 8, 1954 v) w v Wa e/ i 5225a;

I'IIIIIIIII IIIIIIIII llll ATTORNEY United States Patent O METHOD or MAKING TURBOMACHINE BLADING Russell E. Hansen, East Lansing, Mich, assignor to General Motors Corporation, Detroit, Micln, a corporation of Delaware This invention relates to the manufacture of axial flow blading for gas turbine and air compressor turbomachines, such blades being hereinafter referred to generically as turbo-buckets. p

An object of the invention is to cheapen turbo-bucket manufacture by forming the buckets" by a series of inexpensive metal working operations.

Further objects and advantages of the present invention will be apparent reference being bad to the accompanying drawings, wherein a preferred form of the present invention is clearly shown.

In the drawings:

Figure 1 is a perspective view of a billet or that is formed into the invention;

Figure 2 is a section of a at one stage of manufacture;

Figure 3 is a section of an extrusion die with the workpiece at a later stage of manufacture;

Figure 4 is an elevation of the workpiece after removal from the extrusion die of Figure 3;

Figure 5 is a section of the workpiece taken along the line 5-5 of Figure 4;

Figure 6 is a section of an extrusion die with the workpiece at a later stage of manufacture;

Figure 7 is an elevation of the workpiece after removal from the extrusion die of Figure 6;

Figure 8 is a section of the workpiece taken along the line 8-8 of Figure 7;

Figure 9 is a section of a gap roll with the workpiece at a later stage of manufacture;

Figure 10 is an elevation of the workpiece after removal from the gap roll of Figure 9;

Figure 11 is a section of the workpiece taken along the line 11-11 of Figure 10;

Figure 12 is a section of a shearing die with the workpiece at a later stage of manufacture;

Figure 13 is a section taken along the line 1313 of Figure 12;

Figure 14 is an elevation from the shearing die of Figures 12 and 13; and

Figure 15 is a section of the workpiece taken along the line 1515 of Figure 14.

Referring to the drawings, the turbo-buckets are fashioned from cylindrical stock that is sawed into circular sectioned billets 10, as illustrated in Figure 1. The billet is then cold-forged to oval section in a conventional press by dies 12 and 14, as shown by Figure 2. The entire billet is then softened in a conventional induction heater. The particular billet shown is of stainless steel for axial flow compressor blading and may be heated to approximately 2100 F.

The hot oval billet is next placed in a conventional press and partially extruded to rough shape the blade portion to airfoil section, as illustrated in Figures 3 to 5, with the root portion 30 retaining the oval configuration. A punch 16 and a cam 18 are secured to a turbo-bucket in accordance with workpiece of the workpiece after removal from the following description,

forging die with the workpiece tional shot-tumbling machine. The billet root30 is now reheated by a conventional the vertically movable platen 21 and split dies 22 and 4 carrying replaceable inserts 26 and 28 are supported in the fixed die block 32 to accomplish the extrusion. The die block cavity is wider than the split dies 22 and 24 so that the dies can move laterally for engagement with each other to form a matrix shaped in accordance with the shape of the billet as illustrated in Figures 4 and 5. The oval billet is inserted between the dies 22 and 24 and the dies are engaged by lowering the platen to engage the cam wedge surface 34 with the die wedge surface 36. Further lowering of the platen engages the punch with'the billet to force the lower end thereof through the airfoil opening of the inserts 26 and 28 to form the blade portion 20.

In some instances flashing forms on the billet along the split line of the dies. The flashing is removed by a press shearing operation similar to a later described and illustrated press shearing operation.

If necessary, the billet is next descaled in a conveninduction coil to proper softness in the present example) in eration which comprises hot-forging the juncture of the blade and root to finish shape the blade portion 50, as illustrated in Figures 6 to 8. This forging or coining operation is accomplished by inserting the blade portion 20 between the split inserts 42 and 44 of the engageable dies 46 and 48. The dies are brought together on lowering of the platen by engagement of the cam wedge surface 34 with the die wedge surface 52 and the upper ends of the inserts 42 and 44 form a forges the blade portion 50.

Further lowering of the platen accomplishes the next operation which comprises 30 to form the tang 60 and shelf 40. The platen carsocketed end that forms a 48 to finish shape the root portion tang 60, as illustrated in Figures 68.

The billet is then annealed at approximately 1100 F. and descaled in preparation for the next operation which is illustrated in Figures 9-11. The billet is placed in a conventional gap rolling machine wherein gap rolls 56 and 58 are peripherally profiled at 62 and 64 to finish cold-roll the blade portion 20 to airfoil section. Small gap roll cavities 66 and 68 form a button 70 at the end of the blade portion 20 that is used to center the blade during the final grinding operation.

The gap rolling operation produces considerable flash which is removed by a shearing operation shown in Figures 12-15. The billet is first secured in fixed dies 72, 74 and 76 that enclose the blade portion except for flash. The platen 21 is then lowered with a die 78 to shear off the flash. A similar arrangement may be utilized to trim the flashing after the blade extrusion operation, if necessary.

Figures 14 and 15 illustrate the billet after completion of the foregoing operations. The billet is now a substantially finished turbo bucket requiring only heat treatment and grinding for completion.

(approximately 2100 F.

blade portion and a root portion comprising rough shaping the billet to oval section by forging, rough preparation for the next opmatrix that finish hot-extruding the root portion shaping the blade'portion by extrusion; fia slr'tiimriiing basis-gram shapingthe b the blade portion by shearing, finish shaping the blade w portion immediately adjacent the root portion by forging,

finish shaping the root portion by extrusion, finish shaping the remaining blade portion by gap rolling,

ming the blade portion by shearing; p I 2. A process of shaping a circular; sectioned billet into a substantially.

an airfoil sectioned a diamond sectioned shelf next the blade portion and a rectangular sectioned tang depending from the shelf comprising rough shaping the billet to oval section by portion by extrusiom-r finish shapingtheblade portion immediately adjacent 'the forging, rough shaping the blade finish shaping the root portion the remaining blade portion and fiash diamond sectioned shelf next theblade portion and a rectangular sectioned tangdepending from the shelf c0mfinished turbo-bucketthat'; includes balde" portion having a centering button at the free end thereof and a root-portionhaving,

circular sectioned billetwinto" ing, rough shaping the 'iilet' movarseetion*by'stamp: blade portion by extrusion,.fiash trimming the blade portion by shearing, finish shaping the blade portion immediately adjacent the root portion by stamping, finish shaping the root portion by extrusion, finish shaping the remaining blade portion including the centering buttonjby gap rolling, and flash trimming the blade portion by shearing.

References Cited inthe-file' of this patent UNITED STATES PATENTS 1,883, 51 9 Brauchler" Oct. 18, 1932 2,013,622 Bedford Sept. 3, 1935 2,290,734, Bra ssertr Y July.21, 1942 2,577,747 Gibian Dec. 11, 1951 2,638,663 Bartlett May 19, 1953 2,712,688 Steinmeyer July 12, 1955 2,716,270 Gibian Aug. 30, 1955 2,743,509 Friedman May 1, 1956 297663645 Nichols; -a- -Oct. 16; 1956 FOREIGN PATENTS 905,735 France Dec. 12,1945 1,060,577 

